Stem Cells Could Save Endangered Species

Researchers at Scripps Research Institute and the San Diego Zoo worked together to develop stem cells from normal skin cells taken from two extremely endangered species, the northern white rhino and the drill, a type of primate. Those stem cells may someday be used to boost reproduction and cure diseases in the rare animals.

"The best way to manage extinctions is to preserve species and their habitats," said Oliver Ryder, director of genetics at the San Diego Zoo Institute for Conservation Research, in a press release. "but that's not working all the time.

Ryder stated that the northern white rhino is a perfect example of species that could benefit from stem cell technologies. Only seven of the animals exist in the world which makes avoiding in-breeding difficult.

"Stem cell technology provides some level of hope that they won't have to become extinct even though they've been completely eliminated from their habitats. I think that if humankind wants to save this species, we're going to have to develop new methodologies," said Ryder.

The stem cells could eventually be used to create sperm and egg cells for use in artificial insemination.

"I think that work would be a lot easier ethically with endangered species than with humans," said Jeanne Loring, professor of developmental neurobiology at Scripps in a press release, "so I suspect some people working in this area would love to have our cells for experiments."

These newly created stem cells can also be used in disease treatments.

The drill, a primate closely related to humans, was chosen because animals in captivity frequently suffer from diabetes. Researchers are currently working on techniques to use stem cells to treat diabetes in humans, so the close genetic relationship between drills and humans could mean similar techniques will work on both.

To create the stem cells from normal skin cells, the researchers used genetic manipulations. They inserted a gene that caused normal cells to transform into stem cells, a process called induced pluripotency. The scientists used the same gene others had used to make human stem cells from adult cells.

Since the stem cells were developed from common skin cells, there is a ready supply of raw material. And even though the process is inefficient, it doesn't matter, since only a few cells are needed to start a stem cell line.

"The most important thing is to provide these stem cells as a resource for other people taking some of the next steps," said Loring.

Ryder's team at the San Diego Zoo have a bank of candidates for future studies if the rhino and drill stem cell projects prove successful in preserving the species. His team maintains the Frozen Zoo, which contains skin cell samples from over 800 species.

Having a bank of skin cells means that even though an individual animal dies, its unique genetics are preserved. Stem cells made from those skin cells can then be used to re-introduce diversity that would have been lost.